Method of forming sand molds



(No Model.)

s. J. ADAMS.

v MBTHD 0F FORMING SAND MOLDS. Y No. 544,423. Patented Aug. 13,1895.`

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" 1N ihm l UNITED STATES PATENT Ormes..

' STEPHEN JARVIS ADAMS, OF PITTSBURG, PENNSYLVANIA.

METHOD OF FORIVIING SAND MOLDS.

SPGEFIGATN forming part of Letters Patent No. 544,423, dated August 13,1895.

Application tiled November 23, 1891. Serial No. 412,858. (No model.)

To all whom it may concern,.-

Be it known that l, STEPHEN JARvIs ADAMS, a resident 'of Pittsburg, inthe county of Allegheny and State of Pennsylvania, have invented a newand useful Improvement in Methods of Forming Sand Molds; and I do herebydeclare the following to be a full, clear, and'exact descriptionthereof.'

My invention relates to sand-molding apparatus, its object being toprovide a form of apparatus for compactiug the sand closely around thebase of the pattern in such a manner as to avoid spongy parts and allliability of pockets or air-cavities' in the nished mold. There sandmolds are formed by allowing the sand to descend by the force of its owngravity from a point elevated above the ask which contains the patterns,or wh'ere the sand is forced into the flask by the employment ofartificial means, in either case spongy parts, pockets, or air-cavitiesare liable to be formed around the bases of the patterns, due to the airconfined within the flask.V

It is the object of my invention to free the sand molds so formed fromsuch pockets and air-cavities in the manner hereinafter set forth.

My inventipn consists, generally stated, in forming sand molds or coresby first feeding the Sand in bulk by dropping, or similar means, to theask, and then forcing the sand upwardly in the base of the flask tocompact the mold and close any such pockets or aircavities.

To enable others skilled in the art to make and use my invention, I willdescribe the same more fully, referring to the accompanying drawings, inwhich- Figure l is a side View, partly in section, of myimprovedapparatus. Fig. 2 is a like View showing the presser in its raisedposition. Fig. 3 is a view showing the patterns removed, and Fig. etshows the fiask inverted withthe completed molds therein.

Like letters indicate.. like parts figure.

The molding-table A is supported on the floor or platform a, and saidmolding-table is composed of the standards b and the top plate c,supported thereon. The top plate c of said table A is furnished with theopenings d, through which the patterns e may be inserted in each orwithdrawn, aswill more fully hereinafter appear. The patterns e areprovided with rodsf, which act as handles for convenience in theinsertion and withdrawal of said patterns. Above the top platec of thetable A is the pressenplate g, adapted in its normal position to restupon said top plate c. The presser-plate g is likewise furnished withopenings h, which, when said plate is in position, coincide with theopenings d in the top plate c. Vertical rods 'i are secured to thepresser-plate g, and said rods .pass down through openingsj in the topplate c of the table A. The lower ends of the vertical rods 'i aresecured to a guide-plate le, so that any upward movement imparted to thesaid guideplate k will act to elevate the presser-plate g uniformly atvall points of its pressingface. The guide-plate 7c is provided withopenings l, which are adapted to coincide with the openings d and h inthe top plate cl and presser-plate g, respectively. The guides m on theguide-plate k engage with the standards b of the table A and move up anddown thereon. In order to raise and lower the guideplate la and with itthe presser-plate g, a link n is pivoted at or near the center of theguideplate la, the lower end of said link being secured to the end ofthe lever o by means of a pin p, which engages with a slot q in saidlever o. This form of connection between the link 'n andlever o providesforthe requisite amount of play on the part of said link in the raisingand lowering of the guide-plate. The lever o is fulcrumed'at 1' to thestandard b, and said lever may be operatedn by foot or hand power, asmay be found most convenient. Any other suitable form of mechanism forraising and lowering said guide-plate may, however, be employed. `Asupplemental or auxiliary flask or reservoir s rests upon the top platec of the table A, within which the presserplate g is adapted to fitsnugly. The main liask t is supported on the supplemental ask s, thewalls of the former coinciding with and resting upon the walls of thelatter. A chute u or any other suitable feeding device may be arrangedabove the main liask t, by which the sand may be fed in bulk to saidask, such device illustrating any mechanism in or by which a large bulkof sand sufficient to form the entire mold is delivered 'to the flask ata velocity and with force sufficient to pack the sand therein.

I have illustrated and described my invention in connection with its useas applied to the formation of molds for pipe-balls, but its use may beextended lto the formation of any molds or cores to which it may befound applicable.

The operation of my improved molding apparatus is as follows: Then theseveral parts of the apparatus have been arranged, as shown in Fig. l,with the patterns e properly supported within the flasks and thepresser-plate g resting upon the top plate c of the table A, theapparatus is then ready for the molding operation. The sand is then fedin bulk to the flask t, the large body of sand entering the flask at avelocity and with force sufficient to pack, and as the body of sandextends entirely over the flask escape of any great portion of airthrough the mouth of the flask is prevented, so that some air isnecessarily confined within the flask. The sand also descends into thesupplemental flask s, where it finally rests upon the presser-plate g.Upon the descent of the sand in bulk, as above described, this confinedair consequently acts as a cushion for the descending sand. The resultof this action is that spongy air channels and pockets or air-cavities oare formed at or near the lower ends of the patterns e, as shown in Fig.l. Vhen the flask has been properly lled with sand, a cover-plate w isplaced on the flask and confined thereon or it is of sufficient weightto resist the pressure brought to bear on the body of sand from below,as will more fully appear. The outer end of the lever ois then depressedby foot or hand power, which operation, through the connectionsdescribed, will elevate the guide-plate 7c. Since the guide-plate 7c isconnected to the presser-plate g by the Vertical rods t', any verticalmovement imparted to the said guideplate 7c will impart a like movementto the presser-plate g. The action of the presser-plate g as it ascendswill be to compress the body of sand deposited around the lower ends ofthe patterns e and compact it in such manner as to close or destroy anypocket-s or cavities which may have been formed upon the descent of thesand.- It will be noticed that the patterns e are made of a greaterlength than the molds to be formed, ythereby to allow for thiscompacting of the sand up around the line which marks the commencementof the mold proper` To this end the presserplate g reaches its highestpoint of elevation when it arrives at the line of juncture between theflask f and the supplemental flask s, as shown in Fig. 2. The sand isthus uniformly packed within the flask. The cover-plate w acting toresist the pressure from below insures the density of the sand.

Fig. 3 of the drawings illustrates the manner of withdrawing thepatterns after the sand has been compacted, and Fig. 4 illustrates theflask t, inverted ready for the introduction of the cores preparatory tothe casting operation.

What I claim as my invention, and desire to secure by Letters Patent,is-

The herein-described method of forming sand molds, consisting in feedingsand to the flask in bulk and at sufficient velocity to practicallyfinish the packing of the upper part of the mold, and then compressingthe sand in the flask by pressure operating in the opposite direction tothat in which the sand enters the flask, to complete the mold,substantially as set forth.

In testimony whereof I, the said STEPHEN J ARvIs ADAMS, have hereuntoset my hand.

STEPHEN JARVIS ADAMS.

Vitnesses:

JAMES I. KAY, J. N. COOKE.

